Press.



PRESS.

(Applluaa 81011 In. 01.

(llo Iodoh) UNITED STATES PATENT OFFICE.

HENRY E. PRIDMOREOE CHICAGO, ILLINOIS.

PRESS.

SPIEGIFIO ATION forming part of Lettersifatent N0. 658,583, dated September 25, 1900. Aiaplioa.tion filad January s1, 190g. Beria.l m. s,a1s. (N0 model.)

T0 all whom it may concern:

Be it known than I, HENRY E. PR1DMORE, a eilzizen of the United Stabes, residing an Ohicago, in the couuty of Cook and Stare of Il linois, have invented cierain new and useful Improvemenlss in Presses; and I do hereby declare the following 130 be afull, clear, and exaet deseription 0f the invention, such as will enable others skilled in the art to which il: appertaains tso 1nake and use the same.

The invention relates t0 mechanisms for operating the platens of presses and is herein exemplified ineonnection with hand-operated copying-presses, though in view of the obvious adaptabiliby of-the improvements '00- other kinds of presses wibhout intention t o limit or restriet their application 110 any kind of press.

The advantage of -having the platzen of a press move rapidly to the position where the object to be compressed is engaged an 1 then 110 have a slower movemen with increased power for elfeeting the compression has heretofore been reeognized, and it has been proposed '00 employ difierentaial serews for Lhis purpose. So fa.r as I am aware, however, the use of such serews has involved the empl0ymentef clutches of one kind or another for the purpose of securing the neeessary cooperation between the screws 120 efiect the differential movement 0f the platzen. Such elutehes are objeetionable, for the reasons, among obhers, that they complieane the mechanism, reqnire eare and attaention 110 keep them in proper working condition, and in many instances necessitate separate manipulat2ion.

II: is the object: of my invention 130 overeomethese objections and-to produce a mechanism for operating the platzen of presses which when running free of compressing ac- Lion will travel wit-h the quick flow of a simple screw of high pitch, but: whieh when working against resistance will brave! with slower xspeed and increased pdwer Wi1shout the use of a clutch and 110 this end the inven Lion cousis's of the parts and combinations L0 be hereinafter more fully deseribe, and definitely pointed outs in the claims.

In the drawing I have shown the invent;ion as applied to a simple band copying-press, part;s of the same being broken away 110 more follower 01 elearly show the constzructsion and relation of the meehanism within.

The press-frarne A consiss of a.ny usual or suitable form of base a, fr0m which 1'ise the uprights er posts a, preferably joined by t.he cross-arm a Sliding between and preferably guided by the uprights a is the platzen B, between which and the base a the objeet; to be eompressed is placed. The cross-arm a is provided with a screw-Lhread c of high pitch*which is engaged by a corresponding exberiorly-screw-threaded sleeve O free 130 turn thereiri. As shown in the drawing, bhis thread has a pitcbof abont: one L0 -the ineh. The exterior threads c of the sleeve C are omioted from the upper porbion c to nhereby form a guide in direcing the up-and-down move1fienta of the sleeve and prevent wabbling thereof: The interior surfaee of this sleeve is provided with a serew-thread c of relaivelylow pitch, which is engaged by the exterior threads of eorresponding piteh 011 the spindle D, 110 the upper end 0f which is secured the hand-wheel D in any suiable er usual manner such that turning said band-wheel will eause a corresponding movem'entz of the spindle D.- As herein shownbhis thread has a pitseh of abouu eighta to the inch. The spindle D is contin ued beyond the lower end 0f the sleeve and is seeured 150 the p1aten B in a mauner 130 permi rotation of said spindle. In the form of eonnection shown I ha.ve provided the spindle with the enlarged head er ball d and the plaben wih a correspondingly-shaped hemispherieal socket; d, in which said ball resns. Seeured to the platen by the serews d d are the cap-pieces d" d whieh serve 120 retain the ba.ll in the sockets 0f the platzen and eause the lattser 110 rise and fall witah the spindle, as will be obvious. While I have preferred 130 illusbrate this forma of ball and soeket-joint; between the spindle and platen, any form of connecnion which will-permit the spindle 130 turn and yen oarry the platen in its u p-and-down movement may be employed.

Above the connectsion 0f Ishe spindle and plateu I preferably provide the former wibh a flange d, whieh abuts against the sleeve C when the screw is revex-sed 110 lifta the platen, as will be hereinafter referred to, anti above this collar I preferably form 0n the spindle D a guide ring 01' eollar d 120 snugly fit the and sleeve O cause the letzter to tnrn and throngh its high-pitch Lhread conneetion with the eross-arm a of Lhe frame efl?ect a rapid travel of !he platen np or down, aceordingfio the direction of movement of the hand-wheel, the spindle D being rueanwhi-le stationary wih respect 110 the sleeve, and this acbin being due L0 the fa.0t that the pineh 0f Lhe Lhread 0 is so rnuch gre-ater than (hat. of the thread 0 that: Lhere is greater frietion betaween the spindle and the sleev than there is betswe en the sleeve am] its bearing in the frame.

When an objeetsis plaeed beneath the platen to be snbjected t o great eompression, the sleeve is liable to back 06 by being tnrned nnder the wedging action of the high-pitch ohreads unless some provision is made t0 eounteraet this tendenoy, and I have therefore provided high-pitch threaded connection hetween the sleeve and arm a of peeuliar form. The exterior threads 011 the sleeve C have Lhe npper porlsion mhereof beveled, as at f, and the tzhreads in the eross-arm a have nheir upper portions correspondingly beveled, as at f, the lower surfaees of such ihreads being of any usual er preferred formas, for instance, perpendienlar 120 the axis of the sleeve, as a1: f f Therefore when an upward stmain is placed on the sleeve during eornpression the beveled surfaces 0f the Ishreadsare bronghlsforeibly together, eausing the wedging aelaion bhereby produeed 130 inerease nhe resistance 130 upward m0 vement between the sleeve and its bearing snfi'iciently 120 prevent Ishis without adding 110 the resistance -t0 the downward movemenb, which should be as low as possible.

In will be noted gshat the sleeve C is of less lengt h than the shaft D, which exbends entirely through the sleeve, and that when the sleeve has carried the platzen to the point of eompressing achion, and consequ-entaly beeomes stationary the shaft projeclzs a sufi"1- cient distance above the sleeve and cress-arm a to permit movement of the shaft within the sleeve suffieient to accomplish the necessary 00m pression wibhont coming in eontaets w 1th the upper end of the sleeve 01 crossarm a The operation 0f the device is as follows: An article L0 be eompressed having been placed upon the base a beneath the platen the hand-wheelis turned. Owing to the faetthat; more force is required 110 Lurn the spindle in -the sleeve than 1:0 turn the sleeve in its bearn 1g, Lhe sleeve begins to Lurn firsl; and coutanues turning unbil the planen strikes the artsiele in thepress, when the reaetion of the platen incr'eases the friebional resistance of the sleeve in its bearing 130 a point above bhata between the spindle and the threads on the interior of hhe sleeve. The sleeve then stops and the spindle begins to turn with respect to the sleeve, and an y desired degree of 00m pression may be exerted upon the art i0le in the press. In this compressing rnovement the spindle has traveled lengthwise of the sleeve to some extenn, bringing the flange 01 some distance below the lower end 0f the sleeve. On turning Lhe hand-wheel in the opposite direcbion to release the eompression the sleeve is still hold stationary by the wedgin g act.i0n of the bevel-faeed threads and the spindle m0ves upward through the sleeve until the flange d" ahnte against the lower end of bhesleeve, when the latter is taurned backwardly and caused 130 rise with the spindle.

Although 1 have herein shown the relabion between the pioehes 0f the sleeve and thespindle as one to eight, I du n0t desire to be limihed 110 such roportion, in being only neeessary that the piteh 011 the outer threads on the sleeve shall be so far greater 'han that of the threads on the spindle that the resistanee betaween the spindle and the sleeve will be so far superior t0 hat betsween the sleeve and iLs bearing as cause the sleeve (a0 turn firsts when the hand-wheel is revolved 170 lower the platten.

Having thus described my inventaion, what I elaim, and desire o secure by Letters Patent, is-

l. In a diiferential serew mechanism for presses, the combination of a serew-spindle having an operat-ing-haudle and revolubly conneced with the press-platen, and a sleeve bhrongh whieh said spindle is bhreaded wih a low pit-ch, the sleeve working wihh a high pilsch in a correspondingly-lahreaded bearing in the press-frame, and the threads of the sleeve and i1ss bearing in the frame having beveled -upper snrfaces.

2. In a difierential screw mechanism for presses, the combinatiou of a screw-spindle having an operalzing-handle and revolubly conneebed wibh L-he press-platen, and a serew through which seid spindle is Lhreaded with a low piteh, the sleeve working witah a high pinch in a threaded bearing in the pressframe, and. the threads of the sleeve being at such angle 00 the sleeves axis as 120 presen-I; a greater bearing-surfaee on taheir npper sides.

3. In a difierential screw mechanism f0r presses, the combination of a frame having a screw-thread of high pitch, a sleeve having an external thread of like pieh Working berein, and provided with an internal Lhread of relatively-low piteh, a spindle having an operating-bandle and an exterior thread 001- responding 110 the'inbernal thread 0t' the sleeve and working therein, a platen 130 which said spindle is revolubly connected, and a (lange on the spindle adapted 110 engage Lhe lower end of vthe sleeve.

4. In a difierential screw meehanism for presses, the combination f a frame hav1ng a suvew-Lhmad fi \ng\x Weh, a. s\eeve \mvmg an external thread of like pitoh working therein, and provided wih an internal thread of relatively-low pitaoh, a spindle having an exterior thread corresponding '00 be internal thread 0f the sleeve and working therein, a platsen to which said spindle is connected,

1 and a. guide ring 0x collar on the spindle within Lhe sleeve, said sleeve having a unthreaded upper exterior portion.

In a ditferential screw mechanism Mr presses, the combination 0f a frame having a p1ain cross-ba.r provided with a screw-thread of being of greaier lenghh than the sleeve and extending beyond the lattex ab both ende a dxstmxoe sufifxmen m pwm& eompnsssmg movemenfi of bhe spindle wiohout contact of the hand-wheel witah the frame or sleeve.

6. In a difierential screw mechanism for presses, tahe combination of a sleeve having an external bhread of high pitch working in a threaded bearing in a cross-bar 0f the preSS- -frame, a spindle having an operating-handle above the cross-bar and revolubly connected 1:0 the press-platen below the bar, sa.id spindle having an exlaevior thread of low pitch work* ing through the threaded interior cf the sleeve, and an abubment; on the spindle with which the sleeve contacts when the spindle is reversed 120 raise the planten.

In laesimony whereof I aflix my signature in presenue of two winnesses.

HENRY E. PRIDMORE.

Wihnesses:

WM. H. FERGUSON,

CHAS. W. ALLEN. 

